Concrete molding machine



Jan. 8, 1952 N. B. RANDALL 8 1 CONCRETE MOLDING MACHINE Filed March 31, 1949 4 Sheets-Sheet 1 8 N INVENTOR. N0rn zanB.Pandall.

- BY 1 R z /f/bwm/ rim ATTORNEYS 1952 N.' B. RANDALL CONCRETE MOLDING MACHINE 7 Filed March 31, 1949 4 Sheets-Sheet 2 'INVENTOR. NOI'HZGEB. Randall.

A TTORNE Y5 Jan. 8, 1952 N. B. RANDALL 2,582,161

- CONCRETE MOLDING MACHINE Filed March 31, 1949 4 Sheets-Sheet 5 INVENTOR.

IVbrnza zB. Randall.

ATTORNEYS 1952 I N. B. RANDALL 82,161

CONCRETE MOLDING MACHINE I I Filed March 51, 1949 4 Sheets-Sheet 4 INVENTOR. Notnzalz B. Panda ll.

AT TORNEYS Patented Jan. 8, 1952 CONCRETE MOLDING MACHINE Norman Bigelow' Randall, Tacoma, Wash., assignor'to R. C. Draughon and Norman B. Randall,,.b.oth of Tacoma, Wash., as. trustees Application March 31, 1949', Serial No; 84,663

12Claims. 1..

This: invention relates; to; apparatus forv cast.- ing; cementitious' agglomeratesv intomonolithic structural elements: such: as pillars; columns. and like. elongated elements, although it. may alsobe used. forcasting elements of. other shapes ifb desired.

An object of the invention is to provide novel.- meansfor compacting the agglomerates in. the mold so as :to expel'airor. gases from the material and-in such .a. way; as to counteract the; natural tendency oft heavier materials, aggregates. and particles" to: settle inthe mold:

Another object is to: subject thematerial, in the-mold to:a succession of compressive or squeez.-.

ing'; effects from opposite sides the}: compressive force. in; each such. effect begining. at one end i ofthe: mold. and travelling: progressively. toward.- the other'end .in ardirection-opposite to the direction ofifiow of the'materialbeing poured, and opposite to "the effect of gravity on:saidmaterial.

Another object is to combine the aforesaid compacting, or" squeezing: effectwith a: trowelling efiect'on' opposite sides of the casting sothat the. principal. surfaces of the. casting will have a smooth finished appearance. A furtherobjectis tosprovidea novel moldhaving movableswalls that arecompressible for the purposes: andxin. the manner stated above, they moldialso being-inknockdown-forrn such thatit can be-removedquickly andeasily from the cast.- ing-afterthedatter has set or'cured and canine reassembled just as quickly and easily. for further use:

of: the: type characterized above having novel. means.:for lifting and-removing, the poured mold While. at :the same=- timeholding the movable mold walls in proper? molding: position;

Additional objects are'to provide such an apparatus; that isreadily' adjustable for=castings of varying", size. and; shape; that is relatively; simple A still further object is to:provide= apparatus Fig. 2- is a side view. of said apparatus;

Fig. Sis adetailperspective of core supportmg. means;

Figs. land 5 are detail views ofpart of a mold: lifting means;

Fig. 6 isa-sectionalzdetail showing the connection betweensaid liftingmeans and themold;

Fig. '7 is a. verticalsection transverse to the apparatus as .shown in Figs. 1 and 2;.

Fig: 8 is-a perspective. showing details of themold; and

Figs 9- and 10 illustrate; the-finishedcasting.

and the removalsof the. mold therefrom..

v Referring firstto, Figs. 1-, 2- and-T; the apparatus ismounted .ona suitable bed-or table I. supported. We SBIlBSTOf piers 2. or-thelike. Secured to the.-

table I aretwo-base plates' 3 each of whichcarries an oscillating jawas described in detailshereinafter. The molditse1f,. whenin=v pouring posie tion, is located between thejaws and restsonthe inner. margins of the plates 3-;straddling the dividing-space 4 between themsothatthe positions of theplates may beradjusted to accommodate. molds ofdiiferent sizes.

The oscillating. jaws are. pivoted on horizontal axes parallel and closely. adjacent thebase plates.

3. In theformshown (Figs; 1 and '7), longie tudinal-stringers 5 are'securedonthe upper. sur

faces of the-baserplates 3 in any suitablemanner, and. the jaws. filarehingedto thev upper. inner. ed esof.theastringers asshownat. l. The upper surfacesof the stringers. are inclined outwardly anddownwardlyy-as shown;- and the. jawsare cap able ofoscillatingabout-their hinges 1 fromthe upright full line .positionsto the tilted dottedfline,

positions shown in Fig.7.

The configuration and structure of. the mold itself will of course dependuponthe shapeof the casting to be made, and the drawings illustrate a mold forycasting an elongated pillar orcolumn. havingrahollow core andinterlocking. topand.

and the sid'eflangefi. These inserts arelprovidedf with longitudinal. outer grooves 12 and;ridges l3 so asto shape thebottom edge of'the casting into thefemale partof a tongue and groove typeconnection to an adjacent casting,

The. sides of the. mold arev formed. by sheet metal plates I4; thelower. edgesofflwhichare inserted. between .thesid'e flanges 9 of the pallet and:'

the mold inserts I. In the case of the pillar shown in the drawings, these side mold members extend vertically upward when in correct molding position to form flat parallel outer surfaces of the casting. At the top of the casting, the side mold members are bent inwardly at l5 and then shaped to provide inner longitudinal ridges l3 and grooves I? so as to provide a tongue forming the male part of an interlocking connection with an adjacent casting having the configuration produced by the mold inserts II.

The hollow core of the casting is formed by a sheet metal tubular casing is which is slit longitudinally as shown at l9 and rolled to a diameter slightly less than that desired for the opening in the casting so that the slit edges normally overlap somewhat. This core casing is supported in-molding position by mandrels 28 mounted movably on the table l and adapted to enter the open ends of the core casing. In the form shown, laterally spaced parallel rails 21 are secured to the lower side ofthe table I and grooved guide rails 22 are secured to their inner sides. The mandrels are carried by slides 23 movable between the rails 2| and having supporting and guiding ribs 24 which slide in the grooved guide rails 22. The outer ends of the slides 23 carry blocks 25 to which the outer ends of the mandrels 20 are secured above the table i, the ends of the table being slotted to permit the movement of the blocks 25 that is required to move the mandrels 28 into and out of the ends of the core casing. Any suitable means can be employed to effect such movement. As shown,

the lower-sides of the slides 23 carry racks 23 each of which is driven by a pinion 21, reduction gearing 28 and an electric motor 29.

The slit edges of the core casing l8 will normally overlap slightly as stated above, and the mandrels 23 are tapered slightly so that when they are inserted into the core casing, the latter is expanded to the desired size. When thus expanded, an opening formed in the slit edges of the core casing at the approximate center of the machine engages over a similarly shaped keeper post 30 mounted on the central ridge l0 of the pallet. This keeper holds the core casing in its expanded condition after the core mandrels 25 are withdrawn therefrom and while the casting is being cured as hereinafter described. After curing, however, and when the pallet is dropped from the casting as shown in Fig. 10, the keeper 3!] is withdrawn and the slit edges of the core casing may then be overlapped to decrease its size and facilitate its removal from the casting. The inner surface of the core casing may be provided near its ends with suitable hooks 3| (Fig. 7) for use in twisting the casing to overlap its edges and in withdrawing the casing from the casting, and in this case the sides of the core mandrels 20 are grooved as indicated at 32 to slide over the hooks 3|.

The ends of the mold are completed by suit able plates which cooperate with the pallet 8 and side walls 14 and are arranged to permit the mandrels 26 to move slidably through them. In the form shown, vertical end plates 33 (Fig. l) are detachably connected to the pallet by means of studs 34 extending outwardly from the opposite ends of the central ridge ill of the pallet and through openings in the end plates 33, the end plates being held on the studs by means of suitable cotters 35. The width of these end plates is sufficient to close the ends of the molds, taking into account the hereinafter described L plates.

oscillation of the side mold members 14, and hence they extend substantially beyond the side walls when the latter are in their vertical molding positions. However, the end plates 33 may be cut back to less width at the level of the inwardly bent horizontal portions l5 of the side mold members, and these portions may be provided with outwardly extending lugs 36 bent over the cut-back edges of the end plates to restrain them against endwise displacement but slidable along said edges to permit lateral oscillation oi the side mold members. The end plates 33 are provided with circular openings registering with the ends of the core casing Hi to permit the movement of the mandrels 23. Also the circumferences of these openings may be interrupted by one or more projections or lugs extending into the openings and slidably engaging in corresponding grooves in the mandrels. Fig. 1 shows one such lug 31 at the bottom of the opening in the end plate 33, this lug engaging in a groove 38 in the lower side of the mandrel 26. The grooves 38 may also engage over the top of the keeper 39 when fully inserted into the core casing. The groove 38 also prevents vacuum effects which might interfere with withdrawal of the core supports.

The side walls I4 of the mold are flexible about their lower edges, which are held between the pallet flanges 9 and mold inserts ll, so that each side wall may oscillate as a unit with its associated jaw 6. For this purpose the upper edges of the flexible side walls are detachably connected with the jaws by means of channel-shaped cover plates 39 placed on top of the jaws with their depending flanges over the top edges of the side mold members l4 as shown in Fig. 7. Hence when the plates 39 are in place, the side mold members and the jaws are connected for oscillation together about the jaw hinges l. The use of the plates 39 for this purpose has the advan tage of protecting the jaws from overflow of the agglomerate which is poured into the open top of the mold between the inner flanges of the cover Preferably the sides of the jaws 6 are shaped to conform to the configuration of the side mold members 14 over the greater part of their area so as to provide a firm support for the sides of the mold during oscillation and particularly in the molding position shown in Fig. 'I.

The mold can be poured in any suitable manner. For example, a suitable hopper 40 (Fig. 1) is filled with a measured quantity of agglomerate, and when the mold has been assembled in the position shown in Fig. '7, the hopper is moved over the mold and its contents discharged into the open top of the mold, the hopper being thereafter moved back out of the way.

The jaws 6 and side mold walls l4 are oscillated during pouring of the mold and for a desired period thereafter until the mold is ready to be removed and cured. Preferably this oscillation is effected by a suitable number of toggle mechanisms distributed along each jaw, two such mechanisms for each jaw being shown in the drawings.

Brackets 4| are secured to the outer sides of the jaws, and toggle links 42 are pivoted thereto at 43, the other ends of these links are pivotally connected at 44 to toggle links 45, the other ends of which are pivoted at 46 to the upper ends of levers 4T normally standing in the upright position shown in Fig. 7. Toggle operating arms 48 are connected to the toggle pivots 44 at one end, their other ends being pinned at 49 to eccentrics 50 rotating with shafts 5|. These toggle mechg eeaeresr:

5;. anismsaiare? duplicated forr'thez two; jawss and thee twoi-shaftss 5:] J om opposites.- sides'zzof; the: machines are:- driven: in: synchronisnrlinlany suitable mane-- 1161?. Ks; ShWI1'i.,.a-'i. common; electric: motor: 5.2: (Fig'ztmr and: its. worm wheel driveiifaaworm wheel 54 on a central shaft 55. SpI OOKBtSiE'Si-OH? the? shaft-. 55; chains 51;. and zsprocketsr 58-; on the shaftsl ;..ser.veito; drive =thesezshaftsz 51:. inzsyn'a chronism: and :in opposite directions. I

In theroperation of;v the" toggle r mechanismide+ scribed above";-v thei eccentric's cause; vertical reciprocation off thettog-glei operating rods 48 so? that: the; toggle"; joints 44 are:- moved: alternately: above and: below their: neutral.- positions sli'owrr.

im the; drawings;shortening;theetoggleszandroscil- 1 latingtherjawszfi andside moldlmemberssfl abouti thethingesQ 1-; It.will .be'observed that 2the' direc+= tion of flow 'oft the-material dischargednfromtthe hopper: 49;. plus.- the? forces: of: gravity; tends-1 to: cause the agglomerate to flow downwardly; around i the 1 sides: of the=.- cores casing; l8" and". into the:- bottom' of. the) mold:v This motion" of the: material is to a certain extent opposed: by: the: effects of the: oscillating side mold: members: l4: which, afterbeing; withdrawn outwardly, exert -ai squeezing or compressing. effect: on thezmateria'll ass'they 'are swungiiinwardly; again; thescompression. beginning. at the bottom lOf the? mold and moving-i. progressively. upward Thus. the ten-d ency, isPto squeeze thezmaterial-upwardly in fth'e" mold in opposition to its: downward: flow and v to the effect of. gravity; This repeated.squeezingi or: compression.- combine'd withvibrationttendsizto maintainla homogeneous consistency throughout: the: mold material and. to: prevent settling? of: heavy; aggregates; composites or? particles; At theisame'z timeithe. material is compactedi to? crease: its density and. air or: gases 1 are expelled? from": the mold. Also' the principal; surfaces. of;v the. casting? which; in this case include: only." its; two sidesare=:smoothed. toprovidevaasmoothifinsished appearan oer.

When the. molding; operation hasi:be'en*;.com1-.--- pleted'; the=- covers? 39: area. removed? to: disconnect theajaws- 6 from 1 the; side mold members? 14 andtl the j awszarezthen' swung outwardlytofthe":dotted line: position shown in: Fig; 7' so? that the: moldcanibe lifted :out of the: jaws? (theimandrels fltof-f course being withdrawn from the: core casingbl.

Imtheeiomn? shown, this; lateral: withdrawal? of the:jaws is-accomplished'by swingingothmupright levers: 41; about pivots 59: on: suitable; braOketS1iSBi--- cured: to thewtablew 1.. ThGF-IOWBI" en'dsxofi the. levers? are pivotally connected-i at: 60 to: links; 61

the other ends of which are pivotedati B 2iitwthe= a-rms "63:of1 a bell crank lever. mounted loosely on the central shaft 55 as described above. An operating handle: 64 is-f rigidfiwiththe hub of the bell crank. lever. and extends outwardly toone side of'the machine. When; this lever is do pressed, the bell crank is rotated'to pull the lower ends of both levers41"inward simultaneously and thustonwithdraw the .iawsuB to their dottediline positions; The levers 412'0n1 the' same sideof the machine can be. connected for:simultaneou s opera'tionl by the handles 54', as": for example" by means: of? rods. 65.

Before-Y the jaws-are-so withdrawn, however, the-' flexibleeside mold -walls =l 4 -are=suitably'braced or:- supported so that they will= not bulgeor distort when no longer supported by the jaws and during lifting and handling. Preferably this is accomplished by the mold lifting means which, as shown in Fig. 2, comprises a plate 66 having vertical legs 61 depending from its sides and adapted' to: embrace? or; straddle thes mold? thus hold thBISidB. mold 'members'- I4 int. molding:

position; To accommodate. the legs 61) wherrv the lifter: is; lowered onto" the? mold; the? inner. sides; ofipthe; jawsi16 are: recessed. or: slotted-at I58,v each; slot being. of the :propertsize and shape to receive one2of1therlegs: Afterthe covers .39 are-removed;

and while the flexible side walls are still sup portediinmolding: position by the jaws, the lifter" iili..-iszloweredv to insert the'legs 61' in the: slots 68 betweenzthe jaws." andthe side mold. walls, after which" the! jaws are withdrawn laterally as de scribed abovefi.

Preferably the lower ends of? the legs and the pallet. 8areprovided with cooperating engageableec-onnections'fori'lifting the mold" and casting- As: shown: in.Figs'. 4'. and. 5; the

from 1 the jaws. lower. ends: of certain; of; the legs arerecessed 'ancl hoolemembers 69. arel-pivotedat: 10 inthe. recesses? Theehooks'fifi cantbeswung about their'pivots by: rods ll? whichrslide in: grooves'in the legs 61' and project aboverthea top of the lifter'65 where pains of oppositerrods H are. preferably connected for."

simultaneousoperationby cross bars 12; Cover p1ates--=13zenc1ose the rods Hand hooks 6.9.

The palletisiprovidedwith.lugs'which are ar ranged to be; engaged by the hooks 1 Hil on-operat1on:of the" rods." H1. Rails 14' extend along' and are? suitably: secured:- to the side" edges of the"- flanges Qof the pallet; these rails being recessed at-.-l5vto:receive:the hooks 69 and being'provided withalugsr'lfi-s to be engaged' when the hooks are" operated by the.rods 12!: Preferably therails M extendeabove the top. edges of the flanges: 91* and the lower; ends" of the :legs": 67 are notched so asto. providerdependingffeet Tl of reduced thicknesswhichifit betweeni thei'rail's l4 and theside mold?" members M as shown in Fig; 6 3 In this'way the lifter ist= securely" connected: to thepallet to lift 3 theientiretmold. asav unit from thejaws, andlati' ablema'nner; The-pallet" 9' is then free. to drop' from.- the hottom. of the oa si'ng as -indicated in Fig? 1.0? since" there is no contact or adhesion between it and the casting itself. The side mold members I .4 can easily be" removed either before oirafter: dropping the pallet bybending them out wardly to break them away from the sides of the casting asshown in Fig; 9. Ohcethemall'et has been. removed; the -mold inserts l I mayalso" -be:-lo'osenedi andremoved; and" the keeper38 beingwith'drawn from the core casing" l 8, the latter can be extracted bymeans'pfthe hooks 31 The completed ca'sting is then ready for sale anduse'. The mold parts are then cleaned-ifinecessaryand" reassembled for use in' makingianother casting.

It will be understood that in some cases the side walls l4 can. be omitted; the faces of the jaw members beingmadecontinuous (by'omitting th'e recesses: 68)? and? compressing: and shaping memold materialby direct contact therewith f In" such cases the casting is allowed to set up sufficiently while still in molding position to permit removal and handling by the lifter without the support of the side mold Walls, taking into account the fact that the lifter itself may provide While only one embodiment of the inventionv has been described with particularity and illustrated in the drawings, it will be understood that the invention is not restricted to this embodiment but is susceptible of a variety of mechanical expressions, and also that various changes can be made in the form, details of construction, and arrangement of the parts, all without departing from the spirit of the invention. Reference should therefore be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. Apparatus of the class described comprising a pallet, end mold members connected to the'ends of the pallet, side mold members extending between said end mold members and having their lower edges connected to the sides of the pallet, the portions of said side members above their lower edges being oscillatable toward and away from each other, oscillating side supports engag-' ing and oscillating said side mold members, said side supports being withdrawable laterally whereby the pallet and side and end mold members may be removed from the apparatus.

2. Apparatus of the class described comprising a pallet, end mold members connected to the ends of the pallet, side mold members extending between said end mold members and having their lower edges connected to the sides of the pallet, said side mold members being bendable about said lower edges, oscillating means engaging and bending said side mold members to oscillate them toward and away from each other, said oscillating means being withdrawable laterally whereby the pallet and side and end mold members may be removed from the apparatus.

3. Apparatus of the class described comprising a pair of spaced jaws oscillatable toward and away from one another on horizontal axes, a mold located between the jaws and comprising a pallet, end mold members connected thereto, and side mold members extending between said end mold members and having their lower edges connected to said pallet, the portions'of said side mold members above said lower edges being oscillatable toward and away from each other, and means detachably connecting said side mold members and said jaws for oscillating movement together, said jaws when detached from said side mold members being laterally withdrawable whereby said mold can be removed from between the jaws.

--4. Apparatus as claimed in claim 3, said side mold members being flexible for oscillation by said jaws. v

5. Apparatus of the class described comprising a pair of spaced jaws oscillatable toward and away from one another on horizontal axes, a mold located between the jaws and comprising a pallet, upright end walls connected to the ends ofv said pallet, and upright flexible side walls extending between said end walls and having their lower edges connected to the sides of said pallet, the upper portions of said side walls being oscillatable toward and away from each other about said lower edges, a hollow core extending between said end walls, core supporting means movable into and out of the ends of said core through openings in said end walls, andmeans detachably connecting each side wall to one of said jaws for oscillation therewith, said jaws when detached being laterally withdrawable whereby said mold can be removed from between the jaws.

6. Apparatus as defined in claim 5, the faces of said jaws being shaped to conform to and engaging said side walls over the greater part of their area to support the sides of the mold.

'7. Apparatus of the class described comprising a mold having a bottom pallet, upright end walls connected thereto, upright side walls having their lower edges connected to said pallet and bendable about said lower edges for oscillation toward and away from each other between said end walls, and oscillatable means engaging said sidewalls for supporting and os-' cillating said side walls while the mold isbeing poured- 8. Apparatus as defined in claim 7, the upper end portions of said side walls engaging and retaining the upper portions of said end walls against endwise displacement but being slidable laterally relative to said end walls during oscil-v lation of said side walls.

9. Apparatus as defined in claim '7, said pallet having flanged side edges, and'mold inserts located in the bottom of the mold between said flanged side edges, the lower edges of said side walls being engaged between said mold inserts and said flanged side edges of the pallet.

10. Apparatus of the class described comprising a mold pallet, upright end mold walls connected to said pallet, side mold members ex -members and the outer end of the other link having a normally stationary pivot.

12. Apparatus as defined in claim' '11," said outer end of' said other link being pivoted on a' normally stationary lever, and means for swinging said lever whereby the toggle'links pull the"; side moldmember outwardly beyond its' range of oscillation.

NORMAN BIGELOW RANDALL.

-REFERENCES CITED The following references are of record in the file of this patent:

. .UNITED STATES PATENTS Hiatt et a1. Feb.-20, 1940 

